The present invention relates to a liquid ejection apparatus.
Generally, an inkjet printer is known as a liquid ejection apparatus that ejects liquid, or ink, onto a target through a nozzle opening defined in a nozzle-forming surface of a recording head. This type of printer has a wiper member that wipes off ink from a nozzle-forming surface of a recording head for maintenance of the recording head. Such wiping may cause variation in meniscuses of ink in multiple nozzle openings. Further, if the amount of the ink ejected from a certain one of the nozzle openings is comparatively small, the viscosity of the ink may increase in the nozzle opening and thus clog the opening. To solve these problems, as described in, for example, JP-A-2002-86762 and JP-A-2001-30507, a printer having a flushing box has been proposed. Specifically, when printing is not performed, ink is forcibly ejected from nozzle openings of a recording head in response to a drive signal unrelated to printing and received by the flushing box.
More specifically, the printer of JP-A-2002-86762 has a guide shaft, which extends along the longitudinal direction of the printer, and a carriage. A recording head is mounted in the carriage, and the carriage reciprocates along the guide shaft. A cap member is arranged at a home position defined at the right end of the printer and capable of sealing a nozzle surface of the recording head by selectively ascending and descending. A flushing area is defined at the left end of the printer and a flushing box is provided in the flushing area. The flushing box receives an ink absorber. Forcible ejection of ink from the nozzle openings of the recording head into the flushing box, or flushing, is carried out when, in printing, the carriage is moved to the flushing area.
The printer of JP-A-2001-30507 has a rotary drum and an arm member. Each of the rotary drums is located below the nozzle-forming surface of the recording head and rotates about a horizontal axis. The arm member is supported by a shaft of the corresponding rotary drum and caused to be moved by rotation of the rotary drum. The flushing box and the associated wiper members are held by the distal end of the corresponding arm member. Specifically, the recording head of the printer is moved to a non-printing position, which is spaced upward from the rotary drum by a predetermined distance. Then, by causing the arm member to wobble through rotation of the rotary drum, the flushing box and the wiper member are moved to a liquid receiving position. The liquid receiving position is immediately below the nozzle surface of the recording head, which is maintained at the non-printing position.
In this state, forcible ejection of the ink from the nozzle openings of the recording head into the flushing box, or flushing, is conducted. Then, by rotating lead screws, the wiper member is caused to contact and slide on the nozzle surface while elastically deforming. The wiper member is thus moved from a wiping position at which the wiper member wipes the nozzle surface to a non-wiping position spaced from the wiping position to perform wiping. Subsequently, by causing the arm member to wobble, the flushing box, together with the wiper member, is moved separately from the recording head and returned to the liquid non-receiving position. Afterwards, the recording head is lowered from the non-printing position and returned to the printing position, which is close to the outer circumferential surface of the rotary drum.
In the printer of JP-A-2002-86762, the flushing area in which the flushing box is fixed is set at a position opposed to the position of the cap member. The printing area is located between the flushing area and the cap member. Such arrangement of the flushing area increases the size of the printer in the longitudinal direction of the carriage by an amount corresponding to the size of the flushing area.
In the printer of JP-A-2001-30507, the wiper member and the flushing box are held at the distal end of the arm member with the wiper member arranged distally from the flushing box. Therefore, in flushing, the nozzle surface of the recording head and the surface of the flushing box facing the nozzle surface are spaced from each other at least by a margin corresponding to the thickness of the wiper member. Although this configuration prevents the printer from enlarging in the longitudinal direction, it may transform the waste ink ejected from the nozzle openings of the recording head into mist by resistance of the air before the waste ink reaches the flushing box. The mist then floats inside the printer and thus contaminates the interior of the printer.